The editors first learned of stellite delamination in a large valve designed for high-pressure (HP)/high-temperature steam service at the 2009 7F Users Group conference. But all the attention that incident received was a brief mention late in a long user presentation profiling the major inspection of a combined-cycle plant. More than 200 owner/operators were in attendance, yet no questions were asked about the issue-at least none the editors can recall-and it was quickly dismissed. Fig A shows stellite liberated from the seat of a 20-in. hot-reheat block valve installed at that presenter's plant and collected in the strainer for the steam turbine's combined stop and control valve.
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